The Anatomy Department of Duke University has a strong program for the study of biological structure and function with the electron microscope as a major investigative tool. The department combines excellent electron microscope facilities, expertise in freeze-fracture, ultramicrotomy, and frozen hydrated specimen techniques, a unique liquid helium cryomicroscope, and Fourier transform image analysis capability. The department's program for 3-dimensional image reconstructions through electron micrograph tilt data has been developing based upon a home built microdensitometer which is no longer capable of meeting our technical requirements. The increasing use of this densitometer by researchers outside of the department is an indication of the need for an advanced image scanning facility in the Research Triangle area. We are applying for funds to purchase a Perkin-Elmer PDS 1010M scanning microdensitometer and computer hardware to support its use as a shared facility. This instrument will overcome the deficiencies in our current system and provide enhanced capabilities for selection and display of the data.